Objective To explore the diagnostic value of ultrasound-guided puncture biopsy in breast masses.Methods 50 patients were enrolled in this study for breast mass examination and ultrasound presentation of BI-RADS class Ⅳ.All the patients underwent ultrasound-guided biopsy and pathological examination.The pathological results of the biopsy were compared with the final results of pathological diagnosis.The sensitivity and specificity of ultrasound-guided biopsy,and the accuracy of each type of breast mass examination were observed.Results 50 cases of breast masses were successfully punctured under ultrasound guidance,the postoperative pathological results were the diagnostic criteria.The puncture biopsy results showed that 16 cases of benign lesions and 34 cases of non-benign lesions.The postoperative pathological examination results showed that 13 cases of benign lesions,37 cases of non-benign lesions,the sensitivity and the specificity of the biopsy was 89.19％ and 92.31％.Pathological puncture results showed 16 cases of benign tumors with an accuracy rate of 81.25％,27 cases of malignant tumors,the accuracy rate was 92.59％,7 cases of high risk,the accuracy rate was 57.14％.Compared with the accuracy of the diagnosis of benign and malignant results,the diagnostic accuracy of high-risk results was the lowest(x2 =20.802,P ＜ 0.01).Conclusion Ultrasound-guided puncture biopsy can better identify the benign and malignant nature of breast masses,with high accuracy,small trauma,it is safe and reliable,and has important clinical value for the diagnosis of breast mass,which can provide a reliable basis for further clinical treatment scheme.